Accuracy of subjective stats of key performance indicators in tennis
Abstract
The compilation of stats by performance analysis is common in matches with top professional tennis players. However, outside the top level such objectively evaluated stats and feedback for players are rare. With this in mind, we developed an original method that asks players to subjectively evaluate the match stats. This study aimed to investigate the accuracy of subjective stats in tennis. The participants were 30 male collegiate athletes, including some who had participated in national-level competitions. The participants played a 6-game, 1-set practice match, and immediately after the match subjectively evaluated the stats of key performance indicators such as percentages, number of shots, and rally patterns. Objective stats were aggregated using video clips recorded by a digital camera or smartphone. Based on Bland-Altman plots show that subjectively evaluating their own performance indicators helped to confirm the objective stats. Although some variables showed fixed or proportional biases, the mean differences were not significant (percentage of first serve in: 1.733% points; double faults: 0.400 times; net plays: -0.767 times; unforced errors: -2.133 times). These findings support the implementation of a subjective evaluation of key performance indicators in tennis players who might have difficulty incorporating objective evaluations.
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References
Bland, J. M., & Altman, D. G. (1986). Statistical methods for assessing agreement between two methods of clinical measurement. Lancet, 1(8476), 307-310.
Butterworth, A., O’Donoghue, P., & Cropley, B. (2013). Performance profiling in sports coaching: a review. International Journal of Performance Analysis in Sport, 13(3), 572-593. https://doi.org/10.1080/24748668.2013.11868672
Butterworth, D. A., Turner, J. D., & Johnstone, A. J. (2012). Coaches’ perceptions of the potential use of performance analysis in badminton. International Journal of Performance Analysis in Sport, 12(2), 452-467.
Franks, I. M., & Miller, G. (1986). Eyewitness testimony in sport. Journal of Sport Behavior, 9(1), 38-45.
Hardy, B. R. J., Butler, R. J., & Hardy. (1992). The performance profile: theory and application. The Sport psychologist, 6(3), 253-264. https://doi.org/10.1123/tsp.6.3.253
International Tennis Federation. ITN Categories. Retrieved 27 October from http://www.tennisplayandstay.com/itn/itn-categories/itn-categories.aspx
Kolman, N. S., Kramer, T., Elferink-Gemser, M. T., Huijgen, B. C., & Visscher, C. (2019). Technical and tactical skills related to performance levels in tennis: A systematic review. Journal of Sports Sciences, 37(1), 108-121.
Kovalchik, S. (2021). Why Tennis Is Still Not Ready to Play Moneyball. Harvard Data Science Review.
Kovalchik, S. A., & Reid, M. (2017). Comparing matchplay characteristics and physical demands of junior and professional tennis athletes in the era of big data. Journal of sports science & medicine, 16(4), 489.
Kraak, W., Magwa, Z., & Terblanche, E. (2018). Analysis of South African semi-elite rugby head coaches’ engagement with performance analysis. International Journal of Performance Analysis in Sport, 18(2), 350-366. https://doi.org/10.1080/24748668.2018.1477026
Laird, P., & Waters, L. (2008). Eyewitness recollection of sport coaches. International Journal of Performance Analysis in Sport, 8(1), 76-84.
Mitsuhashi, D. (2002). A difference of the subjective analysis and objective analysis in the technical factor of tennis : An examination of the usefulness of a score sheet. Bulletin of Tokaigakuen University, 7, 183-193.
O’Donoghue, P. (2005). Normative Profiles of Sports Performance. International Journal of Performance Analysis in Sport, 5(1), 104-119. https://doi.org/10.1080/24748668.2005.11868319
The R Foundation. The R Project for Statistical Computing. Retrieved August 18 from http://www.r-project.org
Weston, N. J., Greenlees, I. A., & Thelwell, R. C. (2011a). Athlete perceptions of the impacts of performance profiling. International Journal of Sport and Exercise Psychology, 9(2), 173-188.
Weston, N. J., Greenlees, I. A., & Thelwell, R. C. (2011b). The impact of a performance profiling intervention on athletes' intrinsic motivation. Research Quarterly for Exercise and Sport, 82(1), 151-155.
